I needed to find out how can I change my laptop backlight brighness using just a command line. Solution for that problem was easier than I thought because you can do
that just with one line =)

On my laptop which is Dell Latitude D430 brigness file was on /sys/class/backlight/dell_backlight directory but it’s probably almost on the same place /sys/class/backlight/ on every laptop (and linux distribution) which is it possible to change.

Before you start to change your laptop display brightness you should find out which is the maximum brigness of your screen which you can see with cat command from the max_brigtness file like this:

cat /sys/class/backlight/dell_backlight/max_brightness

On my laptop max brightness was 7 and surprisingly lowest brightness is 0 so let’s change brightness between 0-7 =)

So if I want to save energy and turn backlight as dark as possible I just put 0 to brightness file like this:

I used Hiren’s BootCD bootable Linux rescue CD to copy files from that laptop to my clients external harddrive and everything when without a problems.

When I started to move files from that external harddrive to my iMac (Actually to my drobo) I noticed that some (for some reason not all the files on that directory because) files were
locked so I could not move those files… I didn’t want to go thru all the files using graphical user interface so I had to find way to fix those files using command line.

So after a little bit searching I noticed that I can use chflags command to do what I wanted so I started terminal and said:

sudo chflags -R nouchg /Volumes/Drobo/UnCheck

That unlocked all the files from /Volumes/Drobo/UnCheck directory which was exactly what I wanted to do =) I had to do it to couple of other directories too but that was not a hard job
compared to doing all of this using graphical user interface =)